James Dearden - A Kiss Before Dying

Dorothy Carlsson, the daughter of Thor Carlsson, a wealthy industrialist meets her boyfriend at City Hall to get married. But the office is closed so they go to the roof and that's when he kills her by pushing her off the roof. He sends a letter that sounds like she was thinking of committing suicide. And when her father and twin sister, Ellen arrive, all Thor can think of is their family's image but Ellen doesn't thinks she killed herself. And they learn she was pregnant. Ellen would go around trying to find out who got her pregnant but so far no one knows apparently her father was so overprotective he hired someone to keep an eye on her. They guy who killed her hits the road. A few years later Ellen goes to the school to talk to her boyfriend who claims that he's not the one who got her pregnant but thinks he knows who it is. He goes to his apartment to get a yearbook with the man's photo in it but as soon as he gets it the guy shows up and kills him and makes it look like a suicide. Ellen then goes home to her boyfriend, Jay who unbeknownst to her is the guy who killed her sister.